The formula for the standard error of multiple regression coefficients is written incorrectly on the review notes. In the expression for the standard error of the simple regression coefficient, the subscript, by₁
should be replaced by e₁. In the expression for the standard error of the multiple regression coefficient, the subscript, by_1.2 should be replaced by e_.12.

Review session Wednesday 5-7 PM, room 226 Kolh. If you need extra probability help, attend Ty's discussion section Thursday 1:30-3:30. Hicks. Expected Values handout should be available on web now.

NEW NEW NEW Instructions to using STATA and accessing homework data sets:

Beardsley public area computers: (should be running by midday tomorrow). STATA has now been placed in the Application folder. To use data sets,

a)go to Data and Software: Class folders: Soc Science: Economics: Econ 31. Drag/copy file to desktop or user folder.

b) Double click on cps22an (or whatever applicable data set).

c) when computer asks for the correct application to read file in, choose STATA 5. File should open in STATA.

Personal Mac users: (pre 95 computers out of luck). Download software STATA from the server (Data and Software: Class folders: Soc. Science: Economics: Econ 31). Place preferences file in your system's preference file. To use data sets, go to Data and Software: Class folders: Soc Science: Economics: Econ 31. Before double clicking on data set you need to set Stata up to read any file ending in '.dta':

1. From the Apple menu, select Control Panels, then File Exchange
2. Click the 'Add...' button
3. Type dta in the Extension field
4. Scroll down in the Map to: list until you find the Stata application. Click on the Stata application.
5. Click the Add button at the bottom of the Add Mapping window.
To test, locate a stata data file on the Classes server, and double-click its icon. Stata should open up.

PC users: due to extenuating circumstances, we don't anticipate being able to place the PC STATA version on the server until Wednesday. Again, save program and prefs. to hard drive. When accessing data sets, copy from class folder, and then double click (application should open up without any problems).

Some of you are having problems accessing the homework data sets for assignment 2.With the recent reorganization of the server, versions 4.0 (for non powermacs) and PC STATA seem to have been moved. In addition, people working on the public area computers seem to be unable to copy STATA to the desktop (locked pref. file). Unfortunately, we only learned of these problems tonight, and we cannot adjust them until Monday morning. If you do have a power mac, however, you should be able to open the data files with STATA version 5.0.

As a consequence of this computer fiasco, Monday sections will only have PS 1 due this week (with PS2 due next week).Thursday sections will turn in PS2, as planned, on Thursday.

1. Review the section times (listed on the web page) and make sure that you have signed up for one (available either Monday or Thursday). Check out the times and locations; they may have changed/differ from earlier announcements.

2. Problem Set 1 will be due on Thursday for the Thursday section. For people in Monday sections, problem set 1 and 2 will be due Monday. All problem sets will be graded and returned the following week. Homework assignments will not be accepted after the designated discussion section; nor outside of section except for in extenuating circumstances.

3. Stata is available on the server: read the STATA instructions. Discussion section 1, (because no homework assignments will be returned) will be devoted to course bureacracy and STATA troubleshooting/explanations, in addition to general questions about material. We will not review the assignments until they are graded and in your hands (the following week).

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